Re: [PATCH net 2/2] selftests: net: add kTLS async split record regression

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The file descriptor returned by bpf_program__fd() is not validated before use.
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commit d9776d4dbb9fe9a4990835389a529751f93e64af
Author: Christopher Lusk <clusk@northecho.dev>

selftests: net: add kTLS async split record regression

This commit adds a kTLS TX regression test for the BPF sk_msg apply_bytes
split-record path. It verifies that a stream with 512-byte verdict windows
is received correctly, testing both synchronous and async pcrypt providers.

> diff --git a/tools/testing/selftests/net/ktls_async_split.c b/tools/testing/selftests/net/ktls_async_split.c
> new file mode 100644
> index 0000000000000..a9a84e0f5f87b
> --- /dev/null
> +++ b/tools/testing/selftests/net/ktls_async_split.c

[ ... ]

> +static int attach_bpf(const char *obj_path, int sock_fd, struct bpf_object **obj_out)
> +{
> +	struct bpf_object *obj;
> +	struct bpf_program *prog;
> +	int map_fd, prog_fd;
> +	__u32 key = 0;
> +
> +	obj = bpf_object__open_file(obj_path, NULL);
> +	if (libbpf_get_error(obj))
> +		return -EINVAL;
> +	if (bpf_object__load(obj))
> +		return -EINVAL;
> +
> +	prog = bpf_object__find_program_by_name(obj, "apply_bytes_verdict");
> +	if (!prog)
> +		return -ENOENT;
> +	prog_fd = bpf_program__fd(prog);

Should prog_fd be checked for negative values here?

When using manual lookup APIs, bpf_program__fd() can return a negative error
code if the program is invalid. Does it make sense to validate prog_fd before
passing it to bpf_prog_attach(), similar to the map_fd check right below?

> +
> +	map_fd = bpf_object__find_map_fd_by_name(obj, "sock_map");
> +	if (map_fd < 0)
> +		return -ENOENT;
> +
> +	if (bpf_prog_attach(prog_fd, map_fd, BPF_SK_MSG_VERDICT, 0))
> +		return -errno;
> +	if (bpf_map_update_elem(map_fd, &key, &sock_fd, BPF_ANY))
> +		return -errno;
> +
> +	*obj_out = obj;
> +	return 0;
> +}

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Sashiko AI review · https://sashiko.dev/#/patchset/20260515151556.189841-1-clusk@northecho.dev?part=2